400 ECONOMIC INSECTS 



the various enemies of insects into new localities. Some of these 

 have proved successful. Chinch-bugs were in this way kept within 

 bounds by distributing "sick" bugs in fields where attacks were 

 severe. When the weather is favorable this method has proved 

 successful. One notable effort to introduce insect-eating birds has 

 proved disastrous. All are familiar with the history of the English 

 sparrow in America. It was first introduced with the hope that it 

 would be valuable in the destruction of insects, but on reaching 

 the American shores this species reverted to the habits of its 

 ancestors, which lived chiefly upon seeds and grain. While the 

 English sparrow does destroy many insects during the nesting 

 season, it is a grain destroyer much of the time. The main charge 

 against the English sparrow is that it has driven out many of our 

 valuable insect-eating species. 



Potato beetles are injurious both in the adult and larval 

 stages. They were doubtless formerly kept in control by the 

 quail (Bob-white) and other valuable birds which are now too 

 scarce to check the march of such a formidable enemy. Methods 

 of fighting the potato beetle are given in the chapter on potatoes. 



Cotton boll-weevils have made their advance upon the 

 American cotton growing states from the south of Texas. They 

 threaten to spread through the entre cotton belt. Millions of 

 dollars have been spent in efforts to control this enemy. The 

 chief remedies are mentioned in the chapter on cotton growing. 



The corn ear- worm is also called the cotton boll worm. The 

 larvae feed upon young corn ears until they approach maturity. 

 In the southern states they attack cotton plants, feeding upon 

 tender bolls and other parts, if young corn is not available. 

 Remedies were mentioned in the chapter on cotton. In corn 

 growing states north of the cotton belt the ear-worm is a serious 

 enemy, particularly to sweet-corn growers. Fall plowing over the 

 whole neighborhood is perhaps the most practical remedy. Rota- 

 tion of crops will also help. 



Chinch bugs are destructive to small grains, corn and grasses. 

 Both young and adult bugs suck the juices from the stems, begin- 

 ning near the ground and working upward. A remedy some- 

 times practiced by farmers to prevent the spread of chinch bugs 

 is to plow deep furrows around the field that is to be protected. 

 In this furrow drag a log frequently to produce and maintain a 

 fine dust. As the bugs attempt to cross the furrows they are buried 

 in the dust by the use of the log. This method is modified by the 



